* nscd/connections.c (main_loop_poll): Fix handling of read errors

	from inotify.
	(main_loop_epoll): Likewise.

diff --git a/ChangeLog b/ChangeLog
index 148ae59..0aed399 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2008-07-12  Ulrich Drepper  <drepper@redhat.com>
+
+       * nscd/connections.c (main_loop_poll): Fix handling of read errors
+       from inotify.
+       (main_loop_epoll): Likewise.
+
 2008-07-09  Ulrich Drepper  <drepper@redhat.com>
 
        * resolv/res_send.c: Remove unnecessary res_pquery prototype.

diff --git a/nscd/connections.c b/nscd/connections.c
index 0afc95a..e4d32b2 100644 (file)
--- a/nscd/connections.c
+++ b/nscd/connections.c
@@ -1806,42 +1806,64 @@ main_loop_poll (void)
 
          size_t first = 1;
 #ifdef HAVE_INOTIFY
-         if (conns[1].fd == inotify_fd)
+         if (inotify_fd != -1 && conns[1].fd == inotify_fd)
            {
              if (conns[1].revents != 0)
                {
-                 bool done[lastdb] = { false, };
+                 bool to_clear[lastdb] = { false, };
                  union
                  {
                    struct inotify_event i;
                    char buf[100];
                  } inev;
 
-                 while (TEMP_FAILURE_RETRY (read (inotify_fd, &inev,
-                                                  sizeof (inev)))
-                        >= (ssize_t) sizeof (struct inotify_event))
+                 while (1)
                    {
+                     ssize_t nb = TEMP_FAILURE_RETRY (read (inotify_fd, &inev,
+                                                            sizeof (inev)));
+                     if (nb < (ssize_t) sizeof (struct inotify_event))
+                       {
+                         if (nb == -1)
+                           {
+                             /* Something went wrong when reading the inotify
+                                data.  Better disable inotify.  */
+                             conns[1].fd = -1;
+                             firstfree = 1;
+                             if (nused == 2)
+                               nused = 1;
+                             close (inotify_fd);
+                             inotify_fd = -1;
+                             dbg_log (_("disabled inotify after read error"));
+                           }
+                         break;
+                       }
+
                      /* Check which of the files changed.  */
                      for (size_t dbcnt = 0; dbcnt < lastdb; ++dbcnt)
-                       if (!done[dbcnt]
-                           && (inev.i.wd == dbs[dbcnt].inotify_descr
-                               || (dbcnt == hstdb
-                                   && inev.i.wd == resolv_conf_descr)))
+                       if (inev.i.wd == dbs[dbcnt].inotify_descr)
                          {
-                           if (dbcnt == hstdb
-                               && inev.i.wd == resolv_conf_descr)
-                             res_init ();
-
-                           pthread_mutex_lock (&dbs[dbcnt].prune_lock);
-                           dbs[dbcnt].clear_cache = 1;
-                           pthread_mutex_unlock (&dbs[dbcnt].prune_lock);
-                           pthread_cond_signal (&dbs[dbcnt].prune_cond);
-
-                           done[dbcnt] = true;
-                           break;
+                           to_clear[dbcnt] = true;
+                           goto next;
                          }
+
+                     if (inev.i.wd == resolv_conf_descr)
+                       {
+                         res_init ();
+                         to_clear[hstdb] = true;
+                       }
+                   next:;
                    }
 
+                 /* Actually perform the cache clearing.  */
+                 for (size_t dbcnt = 0; dbcnt < lastdb; ++dbcnt)
+                   if (to_clear[dbcnt])
+                     {
+                       pthread_mutex_lock (&dbs[dbcnt].prune_lock);
+                       dbs[dbcnt].clear_cache = 1;
+                       pthread_mutex_unlock (&dbs[dbcnt].prune_lock);
+                       pthread_cond_signal (&dbs[dbcnt].prune_cond);
+                     }
+
                  --n;
                }
 
@@ -1966,27 +1988,57 @@ main_loop_epoll (int efd)
 #ifdef HAVE_INOTIFY
        else if (revs[cnt].data.fd == inotify_fd)
          {
+           bool to_clear[lastdb] = { false, };
            union
            {
              struct inotify_event i;
              char buf[100];
            } inev;
 
-           while (TEMP_FAILURE_RETRY (read (inotify_fd, &inev,
-                                            sizeof (inev)))
-                  >= (ssize_t) sizeof (struct inotify_event))
+           while (1)
              {
+               ssize_t nb = TEMP_FAILURE_RETRY (read (inotify_fd, &inev,
+                                                sizeof (inev)));
+               if (nb < (ssize_t) sizeof (struct inotify_event))
+                 {
+                   if (nb == -1)
+                     {
+                       /* Something went wrong when reading the inotify
+                          data.  Better disable inotify.  */
+                       (void) epoll_ctl (efd, EPOLL_CTL_DEL, inotify_fd,
+                                         NULL);
+                       close (inotify_fd);
+                       inotify_fd = -1;
+                       dbg_log (_("disabled inotify after read error"));
+                     }
+                   break;
+                 }
+
                /* Check which of the files changed.  */
                for (size_t dbcnt = 0; dbcnt < lastdb; ++dbcnt)
                  if (inev.i.wd == dbs[dbcnt].inotify_descr)
                    {
-                     pthread_mutex_trylock (&dbs[dbcnt].prune_lock);
-                     dbs[dbcnt].clear_cache = 1;
-                     pthread_mutex_unlock (&dbs[dbcnt].prune_lock);
-                     pthread_cond_signal (&dbs[dbcnt].prune_cond);
-                     break;
+                     to_clear[dbcnt] = true;
+                     goto next;
                    }
+
+               if (inev.i.wd == resolv_conf_descr)
+                 {
+                   res_init ();
+                   to_clear[hstdb] = true;
+                 }
+             next:;
              }
+
+           /* Actually perform the cache clearing.  */
+           for (size_t dbcnt = 0; dbcnt < lastdb; ++dbcnt)
+             if (to_clear[dbcnt])
+               {
+                 pthread_mutex_lock (&dbs[dbcnt].prune_lock);
+                 dbs[dbcnt].clear_cache = 1;
+                 pthread_mutex_unlock (&dbs[dbcnt].prune_lock);
+                 pthread_cond_signal (&dbs[dbcnt].prune_cond);
+               }
          }
 #endif
        else
@@ -2010,8 +2062,10 @@ main_loop_epoll (int efd)
       /*  Now look for descriptors for accepted connections which have
          no reply in too long of a time.  */
       time_t laststart = now - ACCEPT_TIMEOUT;
+      assert (starttime[sock] == 0);
+      assert (inotify_fd == -1 || starttime[inotify_fd] == 0);
       for (int cnt = highest; cnt > STDERR_FILENO; --cnt)
-       if (cnt != sock && starttime[cnt] != 0 && starttime[cnt] < laststart)
+       if (starttime[cnt] != 0 && starttime[cnt] < laststart)
          {
            /* We are waiting for this one for too long.  Close it.  */
            (void) epoll_ctl (efd, EPOLL_CTL_DEL, cnt, NULL);